Topical Formulation with Niacinamide Combined with 5 MHz Ultrasound for Improving Skin Ageing: A Double-blind, Randomised, Placebo-controlled Clinical Study

Introduction: Skin ageing is a complex process influenced by various factors. Personal care products claim to address ageing signs, yet clinical efficacy tests lack standardised regulations. Niacinamide (NIA) is known for skin benefits, including managing hyperpigmentation and enhancing the barrier function. The 5 MHz unfocused ultrasound (5-US) is a technological intervention for cutaneous ageing, lacking sufficient literature. This study aimed to clinically assess a topical formulation with NIA, combined with facial application of unfocused 5-US. Methods: Sixty-seven female subjects (30-60 years) with signs of aged skin participated in the study. They were enrolled and randomised into four groups: (A) placebo formulation, (B) cosmetic formulation, (C) placebo formulation plus 5-US, and (D) cosmetic formulation plus 5-US. Groups C and D performed the aesthetic procedure of 5-US on the entire face, in a total time of 20 minutes per session, once per week (eight total sessions). Clinical, instrumental, and subjective assessments were performed before (T0) and during the eighth week (T8) of the study. Results: The formulation with NIA improved stratum corneum aqueous content and reduced transepidermal water loss. Sebum reduction was observed in groups utilising the formulation. Consumer evaluations indicated improvements in appearance, firmness, elasticity, and reduced wrinkles, notably in Groups C and D. Sensory analysis indicated overall product acceptability. Conclusion: The formulation with NIA improved skin hydration and reduced sebum content in mature skin, while subjective evaluations indicated qualitative improvements in skin appearance. Although 5-US alone did not show instrumental improvements, protocol adjustments and longer study periods may yield better results. The comprehensive approach provides an innovative perspective into potential synergies, suggesting future directions for anti-ageing interventions in skin care.